While I’ve run many games over the years at this point I run far fewer. Currently my 5e Dungeons & Dragons game is on a short hiatus as I take a break to recharge myself. It is set in the now multi-decade campaign setting for my fantasy games – the world of Uerth. It is, if I say so myself, a somewhat unique setting in that is based on a planetary setting – it’s a set of recursive interconnecting realms with it’s own unique cosmology that has it’s roots in some of my very earliest D&D games. It’s been run with AD&D 1E, now 5E, but I also ran it with a heartbreaker homebrew for years, and even a couple of very limited trials with other games systems.
But I also run a Call of Cthulhu game occasionally, and that is what I’m running currently. But it’s a very pulpy setting using elements from a series of old stories and serials from that era, in addition to the Call of Cthulhu 7E rules I’m also using the Pulp Cthulhu rules as well. Over the years I’ve run Classic Era, Gaslight, and Modern – plus I’m a huge fan of Delta Green – but my last “pre-campaign” was set in Paris during Great War with the Investigators playing members of the American Expeditionary Force, setting up the current campaign set in Chicago.
I also run Cyberpunk 2020 and Traveller. For years I ran a hybrid game that I set in a vaguely canon Traveller universe but using the CP2020 rules, currently I’m in the process of switching over to Mongoose Traveller and finally breaking down and creating my own campaign based on a more Proto-Traveller setting rather than the full glory that is the canon Third Imperium.
For Cyberpunk 2020 I simply love the classic Night City setting along with the larger world as written up in canon, even if some of the flavor text of the game has been superseded by the real world. While the game is essentially a dead property (though I’m looking forward to the 2077 computer game) it was very, very popular there for awhile it’s kind of dead now. That said, there was (and still is) a whole ton of stuff on the Internet for it.
The last game that I (and my spouse) ran the crap out for awhile there was a modern occult-horror game we called “Chicago Unseen.” We used 2e World of Darkness rules (mainly Mage) for years before we were finally crushed under the weight of that utterly broken system (and attempts to make sense of the bewildering and conflicting canon). If/when we pick that game up again we’re going to use the 2e Witchcraft / Armageddon (Unisystem) rules and adapt the heck out of them. We loved the setting and the characters we developed, but the rules finally killed it for us.